I followed iClarified's tutorial and created the custom firmware (iPhone1,2_3.1.2_7D11_Custom_Restore). When I open iTunes it says the iPhone is in recovery mode, so I select the custom firmware. iTunes displays "Preparing iPhone for restore...", and it just sits there. Eventually an error pops up in iTunes, "iPhone could not be restored. Unknown error occurred (1604). I have already restored to Apple's original firmware (which works fine), then using PwnageTool and the custom firmware three times now, and I keep having the same problem. Also restarted the Mac a number of times as well, just in case. What am I missing?